Appendix D - Flood Assessment

R1593: FLOOD ASSESSMENT – 9A JIRRIMA CRESCENT, COOROIBAH



TABLE OF CONTENTS                                              TABLE OF FIGURES
1    SCOPE                                                 1
     1.1. GUIDELINES                                       1   FIGURE 1 – SITE LOCATION (EXTRACT FROM NOOSA PLAN 2020) ......................................................................... 1
     1.2. REVISION                                         1   FIGURE 2 – ZONE MAP (EXTRACT FROM NOOSA PLAN 2020) ................................................................................. 1
                                                               FIGURE 3 – PROPOSED SITE LAYOUT............................................................................................................................... 2
2    PROJECT DESCRIPTION                                   1
     2.1. LOCATION & LANDUSE                               1   FIGURE 4 – EXTRACT FROM NOOSA PLAN FLOOD HAZARD OVERLAY MAP ..................................................... 2
     2.2. PROJECT WORKS                                    2   FIGURE 5 – CATCHMENT PLAN.......................................................................................................................................... 5
                                                               FIGURE 6 – XP MODEL FEATURES ..................................................................................................................................... 7
3    SITE DESCRIPTION                                      2
     3.1. TOPOGRAPHY AND DRAINAGE                          2   FIGURE 7 – EXTRACT FROM 1 % AEP AFFLUX PLOT .................................................................................................... 9
     3.2. FLOODING                                         2   FIGURE 8 – 1 % PEAK WATER LEVEL ............................................................................................................................... 10
                                                               FIGURE 8 – 1 % PEAK WATER LEVEL ................................................................................................................................ 11
4    OVERLAND FLOW ASSESSMENT                              3
     4.1. HYDROLOGY                                        3
           4.1.1. RAINFALL DATA                            3
     4.2. CATCHMENT DELINEATION                            3   TABLE OF TABLES
           4.2.1. ROUTING                                  4
           4.2.2. ROUGHNESS COEFFICIENTS                   4   TABLE 1 - INTENSITY FREQUENCY DURATION DATA APPLIED TO HYDROLOGIC ASSESSMENT .................. 3
           4.2.3. RAINFALL LOSSES                          4   TABLE 2 – CATCHMENT DETAILS APPLIED TO HYDROLOGIC ASSESSMENT ....................................................... 3
     4.3. RATIONAL METHOD COMPARISON                       4   TABLE 3 – SUMMARY OF RATIONAL METHOD COMPARISON – 1 % AEP ............................................................ 4
     4.4. HYDRAULIC MODELLING                              6
           4.4.1. BOUNDARY CONDITIONS                      6
           4.4.2. ROUGHNESS                                6
           4.4.3. 1D ELEMENTS                              6
     4.5. RESULTS – FLOOD MAPPING                          8
     4.6. RESULTS – DRIVEWAY FLOODING                      8
5    SUMMARY                                               8
APPENDIX A                                                 A
APPENDIX B                                                 B
APPENDIX C                                                 C




Environment. Engineering. Education.                                                                                                                                                                                     PAGE I